Wrapping machine



April 27,-1937. F. c. BUSCHE WRAPPING MACHINE Filed Aug. 5, 1955 3 ShetS-Sheet 1 INVENTOR fkiom/cx 6. 5086/75 BY (Mr =1, ATTORNEY A ril 27, 1937. F. c. BUSCHE 7 1 WRAPPING MACHINE Filed Aug. 5, 1935 3 Sheets-Sheet 2 :E'IELE INVENTOR v f/vipnwck 6. 60.5mm

BY 3 (HM/K ATTORNEY Patented Apr. 27, 1937 UNITED STATES PATENT OFFICE 11 Claims.

This invention relates to mechanisms for applying protective wrappings to objects.

It is an object of the invention to provide a machine for wrapping an object in a protective envelope without the necessity of pre-forming the envelope.

Another object of the invention is to provide a machine which will in a single operation apply and seal a protective envelope about an object using unprepared sheets of wrapping material.

A further object of the invention is to provide a machine of the character described which will apply, to the object to be wrapped, a substantial- 1y uncrumpled, form-fitting envelope.

The invention possesses other objects, and features of advantage, some of which together with the foregoing, will be set forth in the detailed description of the invention which follows, however it is to be understood that the invention is not to be limited to the specific form thereof shown and described as various embodiments thereof may be employed within the scope of the appended claims.

Referring to the drawings:

Figure l is a side elevational view of the machine of my invention.

Figure 2 is a top plan view of the machine.

Figure 3 is a side elevational view of the upper portion of the machine showing the positions of the parts thereof when the sealing head is contacting the die.

Figure 4 is an enlarged view, partly in section and partly in side elevation, showing the positions occupied by the object to be wrapped, and the sheets of wrapping material, prior to the sealing operation.

Figure 5 is an enlarged view, for the most part in section, of the sealing head and die in position to seal the wrapping material about the object to be wrapped.

At the present time the waterproof type of cellophane is enjoying widespread use as a wrapping material due, in a large measure, to three reasons; first, to its imperviousness to moisture, thereby affording a maximum of protection, to the contents of the package against spore formation therein; second, to its ability in a properly sealed package, to protect the contents of the package against contamination by bacteria, and third, to its high degree of transparency, which permits the goods to be displayed to its full advantage. I

The problem, in the use of this material for A wrapping purposes, has been in the matter of hermetically sealing the package. There seems to be no generally known substance which, when used as a bonding agent, will cause intimate union of pieces of the material, and as a result, most users, at the present time, are employing a tacky adhesive for sealing their packages as substances of this nature seem to be the only agents possessed of suflicient tenacity to maintain the edges of the package together.

Sealing packages with these tacky adhesives however, does not insure that the goods will be protected until they reach the consumer, for due to rough handling of the package or the exposure thereof to abnormally high temperatures, such as direct sunlight, which will soften the adhesive and consequently lessen its holding power, the sealed joints are sometimes separated which will, of course, provide an opening in the wrapper through which contaminating matter may enter and spoil the goods.

Another undesirable feature is that in wrapping goods which have a form other than that of a rectangular prism, the wrapper, in order to conform to the shape of the goods, must be considerably crumpled with the result that a plurality of surfaces are formed on the wrapper which are capable of intercepting and reflecting light rays. Thus a customer, who is approaching a display of goods so wrapped, will have his vision partially obscured, by the light reflections from the wrappers, and will be unable to ascertain what the contents of the packages are unless he moves into a position wherein his body, will intercept the light rays causing the reflections, or unless he moves to a position which will permit close range inspection of the packages.

I have provide a machine which not only completely seals an enveloping Wrapper about an object, by fusing the joined edges of the wrapper together, but which also causes the wrapper to be positioned in intimate contact with the surface of the article thereby obviating the undesirable light reflecting surfaces in the wrapper mentioned above and providing a package which, due to being hermetically sealed, will exclude bacteria and other contaminating matter and maintain the contents thereof in a fresh state over a greater period of time.

In detail, the packaging machine of my invention comprises a rectangular frame having vertically disposed legs 6 joined together at their upper ends by a top frame 1, adjacent their lower ends by a bottom frame 8 and midway of their lengths by an intermediate frame 9. All of the frame members are joined together preferably by welding.

Secured to the upper surface of the top frame I, by means of screws I0, is a plate II on which is mounted, by the screws l2, a die ring 13. As will be seen, in Figures 4 and 5, the die ring is provided with a central aperture I 4 which is counter-bored to provide a circular recess l5 which receives the flange I6 of a die H. ,The flange I6 is of slightly greater thickness than the depth of the recess l5 so that, by tightening the screws l2, the flange is clamped between the bottom of the recess and the surface of the plate H thereby locking the die in position.

The portion of the die periphery, adjacent the aperture 14 of the die ring, is reduced in diameter so as to provide an annular slot l8 about the die and the upper surface of the die is provided with a concavity [9 whose brim merges into a corrugated flange 20 formed along the inner edge of the annular slot l8.

Mounted at the rear edge of the plate II is a bracket provided with a pair of vertically extending side members 2| having a shaft 22 secured therein which provides a pivotal mounting for a pair of arms 23. One end of each arm 23 is provided with an aperture which receives a pivot pin 24 secured to the housing 25 of a sealing head normally maintained as is shown in Figure 1, above the die by the counter-weight 26 which is attached to the other end of the arm 23 by means of screws 21. A pair of radius arms 28 are provided, each of which is pivotally secured to both the housing 25 and the bracket side members 2!, by means of pivot screws 29, and is disposed in parallelism with that portion of the arm 23 connecting the housing and the side members.

As will be seen clearly in Figure 5, the sealing head housing 25 is cup-shaped, being provided with a cylindrical side wall 30 and an end wall 3| formed integrally therewith.

The open end of the housing is counter-bored to provide an annular recess 32 in which is secured, by means of a plurality of rivets 33, a cylindrical trimming knife 34 provided with serrations 35 along its exposed lower edge.

The inner ends of the rivets 33 are countersunk so that a flush inner bore 33 is provided in the housing in which is slidably mounted a tubular plunger 3? provided, on its lower face, with corrugations 38, which are adapted to nest with the corrugated flange 20 of the die, and at its upper end, with an end plate 39. A plurality of screws 43 are tapped into the end plate and pass, slidably, through apertures formed in the housing end wall 3!. Springs 4! are provided about each of the screws and are disposed between the end plates 3! and 39 for urging the plunger downwardly in the housing bore 36.

Means are provided for moving the sealing head into engagement with the die so as to nest the corrugations of the die and plunger and cause the trimming knife 34 to enter the slot l8. Secured to the bottom frame 8 is a cross member 42 provided with a pair of downwardly ex tending brackets 43 each having a bolt 44% therein which serves as the pivot pin for each of a pair of treadle bars 45. The forward end of the treadle bars are joined by a cross bar 46 and a foot plate 4'! and the bars are each provided with rearwardly extending arms 48 whose distal ends are provided with bolts 49 pivotally secured to each end of a tie-bar 50. The center of the tiebar is apertured to receive one end of a connecting rod 5| and the upper end of this rod is se cured by means of nuts 52 to a tie-bar 53 pivotally mounted, by means of the bolts 54, on the arm 23 at a point spaced from the axis of the pivot 22 thereof. The lower end of the connecting rod is provided with a pair of coil springs 55 and 56, the former of which is disposed between the upper surface of the tie-bar and the face of a collar 5'1, secured on the rod by means of a setscrew 58, and the latter of which is disposed between the lower surface of the tie-bar 50 and the face of a nut 59 threaded on the end of the rod. A resilient connection is thus provided between the treadle bars 45 and the connecting rod 5|.

From the description thus far it will be seen that by pressure applied to the foot plate 41 by the operator the treadle bars 45 will be swung downwardly about the pivot pins 44 causing the arms 48 to move upwardly and, through the connection of the latter with the arms 23, by means of the connecting rod 5|, causing the arms to swing about the pivots 22 and lower the heater head into contact with the die as is illustrated in Figure 3. The purpose of the spring construction about the lower pivotal connection of the connecting rod and the arms 48 is to preclude the possibility of damage occurring to the members of the die and heater head when they are brought together should, by accident, any solid object be present between the mating portions of these portions of the mechanism.

Means are provided for effecting a multiplication of leverage when the heater head is adjacent the face of the die so that considerably more pressure may be obtained between the head and die than could be had if the operation of the device was controlled solely by the connection between the treadle bars and the arms 23 by the connecting rod. This multiplication of leverage also serves to lessen the effort of the operator necessary to actuate the device and consequently fatigue of the operator is not hastened.

It will be noted, particularly in Figure 1, that the upper edge of each arm 23 lying between the pivots 22 and 24 is shaped to provide a sloping cam surface as upon which is disposed a roller 6! carried on the end of long lever 62 whose lower end is pivotally secured to the treadle bar 45, forward of the pivot 44, by means of a pivot bolt 63. A shaft 64, secured in the intermediate frame 9, journals a bell-crank having a lower arm 65 and an upper arm 66, the arm 65 being connected by means of a link 61 with a rod 68 extending between the treadle bars 45 and the arm 66 being connected, by means of a link 69 with a rod Ill, disposed between the levers 62.

When the treadle is depressed, as was explained above to bring the sealing head into contact with the die, the downward movement of the treadle bars 45 will cause movement of the bellcrank and will cause the levers 62 to move forward, thereby moving the roller 61 along the cam surface 53. The degree of slope of this surface and the leverage ratios between the parts of the mechanism for moving the levers 62 are such that the roller 6| will be in contact with the surface during the downward movement of the arms 23. As the sealing head contacts the die surface the upward movement of the connecting rod 5| is halted, continued movement of the arm 48 merely compressing the spring which pressure will, of course, be transmitted through the parts to the contacting surfaces of the sealing head and the die. However, due to the positive connection between the treadle and the levers 62, the rollers 6| will continue to be moved along the cam surfaces 60, which will, due to the slight degree of slope of the latter, cause pressure to be applied to the contacting surfaces in a greater degree, and in a more gradual man ner than would be the case if the application of pressure were obtained solely through the connecting rod 5!.

Let us now consider the operation of the machine in applying and sealing a protective wrapper to an object. In Figure 4 I have shown the sealing head in the position it normally occupies above the die prior to the start or its movement into contacttherewith, and an object, which may be considered, for exemplary purposes, to be a pastry product, such as a small cake or pie II, disposed centrally of the die between sheets 12 of cellophane or other similar sheet material. The sheets Hare of such dimensions that they extend outwardly beyond the slot 18in the die.

The object to 'bewr'apped, and the sheets-of wrapping material being properly placed, the operator now steps on the treadle, causing the sealing head to move downwardly toward the die, whereupon the corrugated face of the plunger 37 will contact the upper sheet of wrapping material "and will draw it downwardly at the same time tensioning it, and forcing the object and the lower sheet of wrapping material into the concavity, IQ, of the die, thereby also tensioning the 'lower sheet. The downward movement of the sealing head is continued until the corrugations of the plunger nestwith'th'ose of the die, whereupon both sheets of wrapping material will be clamped between the corrugated surfaces. Additional pressure on the treadle will cause the housing 38 tocontinue downwardly relatively to the plunger which will cause the trimming knife 34 to enter the slot 18, as shown in Figure 5, and trim the wrapping'sheets' to circular form, the serrations on the knife edge being provided to facilitate the separation of the portions of the sheets enclosing the object from the waste wrapping material as the tearing action provided by the serrations requires'a lesserexpenditure of power than would a straight shearing cut. Means are provided for applying heat to the clamped portions of the wrapping sheets so as to effect fusion of the contacting surfacecoatings thereof and consequently hermetically seal the object in the wrapper Secured on the inner surface of the plunger end wall 39, by means of screws 13, is a block of insulating material M having a heating element 15 embedded therein. This element may be constructed in the usual manner, of resistance wireor strips, each end of which is electrically connected with a terminal screw 16 which passes upwardly through an insulating bushing 11 secured in an aperture formed in the plunger end wall. A cord 18 containing a pair of conductors l9, which are con n'ected respectively to each of the terminal screws by nuts 80, is providedfor connecting the heating element with a suitable source of current.

When current flows throughtheelement 15 the heat radiated thereby Will be absorbed by the plunger and will beconduct ed by the wall '31 thereof to its corrugated edge, whereupon the clamped edges of the wrapping material will be heated and the coatings thereof melted sufiiciently to cause fusion thereof. As soon as this occurs, which ordinarily does not require more than a few seconds, the pressure on the treadle is released and the sealing head is raised partly by the gravital action of the counter-weight 26 and the action of a spring 8| connected between the treadle bars and a bracket 82 secured to the frame. This spring also acts through the links 67 and 69 and the bell-crank, to restore the lever 62 and the roller 6| to; their normal positions. I i

It is desirable that the machine'be adjustable so-that sealing heads and ,dies of different sizes may be mounted thereon to permit wrapping and sealing of objects having different sizes or shapes. To facilitate this the portions of the arms 23, lying between the pivots 22 and 24, and the radius arms spoken of.

28 are separated; the portions of each arm corinected with the sealing head being provided with an elongated slot 83 through which screws 84 pass'and are tapped into theother portions of the arms. This construction allows the lengthening or shortening of the arms to move the sealing head so that it will properly mate with the die.

It is also desirable that the -movementfof th'e sealing head housing relative to the plunger be limited so as to control the amount that the trimming knife 34 enters the slot I8. This'is done by providing a setscrew 85 tapped into the housing end wall 3| and provided with 'a rounded end which contacts the plunger en'd'wall'when the lower limit of movement of'the housing has been reached. A lock-nut 86is provided onthje setscrew for maintaining the adjustment of the latter;

Withthe packaging machine of myinv t just described it is possible to wrap and com- Jpletely seal'objects 'in'a minimum of time'thereby enabling the device to be used in factories or establishments where it is necessary that a wrap}- ping machine be used which will keep pace with the machines which produce the objects sothata production efliciency'may be mainhigh degree of tained. g r

In addition to being capable'of rapid operation, the machine produces a package'which is very pleasing to the eye, the wrapper sriuglyffitting 1 the object and being devoid of any portions crumpled to a considerable degree which; as was discussed above, would, when the merchandise is on display, cause the" undesirable light reflections entire package are 'adjacentthe' sealed "edges thereof, and these are not unsightly, being more or less regularly pleated, caused by the corrugations of the plunger en'd'as it descendsto seatin 'thedie. PI

The most important feature of the package, however, lies in' the fact-that thesealing thereof'is'accomplished' by fusion and no amount of rough handling or temperature change" is liable to rupture the seal and permit entry into the package of bacteria or other contaminating matter. 'In fact, under test, it was found that the main portions of the wrapper would tear before the sealed edge of the package would open. I'claimr l; A packaging machine for applying and sealing an envelope about an object comprising 'a frame,a die for supporting an object to be wrapped and sheets of wrapping material thereon, secured on said frame, an arm 'pivotally mounted on said z;

frame, a sealing head mounted on said arm and positioned adjacent said die, a treadle pivotally mounted on said frame, means for resiliently connecting'sai'd arm and treadle for movement to-' gether to move said sealing head into contact with said die, and means movable longitudinally of said arm for pressing said seal'ing'head'and die together.

2. A packaging machine for applyingand seal: ing an envelope about an object comprising a frame, a die for supporting an object I to-be wrapped and sheets of wrapping material thereon, secured on said frame, an arm pivotally' mounted on said frame, a sealing head mounted on said arm and positioned adjacent said die, a treadle pivotally mounted on said rrameymeans for resiliently connecting said arm and treadle for movement together to move said sealing head into contact with said die, and a roller connected. with said treadle and movable when said treadle The y irre ular Surfaces onthe is moved, along said arm for pressing said sealing head and die together.

3. A packaging machine for applying and sealing an envelope about an object comprising a frame, a die for supporting an object to be wrapped and sheets of wrapping material thereon, secured on said frame, an arm having an inclined edge pivotally mounted on said frame, a sealing head mounted on said arm and positioned adjacent said die, a treadle pivotallyrmounted on said frame, means for resiliently connecting said arm and treadle for movement together to move said sealing head into contact with said die and a roller mounted for movement with said treadle and movable along the inclined edge of said arm for pressing said sealing head and die together.

4. A packaging machine for applying and sealing an envelope about an object comprising a frame, a die for supporting an object to be wrapped and sheets of wrapping material thereon, secured on said frame, an arm having an inclined edge pivotally mounted on said frame, a sealing head mounted on said arm and positioned adjacent said die, a treadle pivotally mounted on said frame, a connecting rod pivotally secured at one end thereof to said arm and at the other end thereof resiliently connected with said treadle for connecting said arm and treadle for movement together to move said sealing head into contact with said die, a lever pivotally mounted on said treadle and extending toward said arm, a roller journaled on said lever and contacting the inclined edge of said arm, a bell-crank pivotally mounted on said frame, and links connecting said bell-crank and said treadle and said bell-crank and said lever whereby when said treadle is moved said lever is moved relatively thereto and said roller is moved longitudinally of said arm along the inclined edge thereof to press said sealing head and said die together.

5. A packaging machine for applying and sealing an envelope about an object comprising a frame, a die for supporting an object to be wrapped and sheets of wrapping material thereon, secured on said frame, a pair of parallel arms pivotally mounted on said frame, one of said arms having an inclined edge thereon, a sealing head mounted on each of said arms adjacent said die, means for extending said arms to adjust the position of said sealing head relative to said die, a treadle pivotally mounted on said frame, means for resiliently connecting said treadle and one of said arms for movement together to move said sealing head into contact with said die, a roller contacting the inclined edge of said arm and movable therealong to press said sealing head and die together and means for connecting said roller for positive movement with said treadle.

6. A packaging machine for applying and sealing an envelope about an object comprising a die for supporting an object interposed between sheets of wrapping material provided with fusible surfaces, a movably mounted sealing head housing, a tubular plunger movably supported within the housing and having a portion engageable with said die, means for moving said housing so as to engage the plunger with and disengage it from said die, and means operated by relative movement of the housing with respect to the plunger for applying yieldable pressure to the latter while engaged with the die.

'7. In a packaging machine for applying and sealing an envelope about an object, a die for supporting the object to be wrapped between sheets of wrapping material provided with fusible surfaces, a sealing head housing, a plunger carried by said housing and mounted to reciprocate therein, said plunger having a portion complemental to said die, and means for yieldably limiting relative movement of the plunger and housing in one direction, and positively limiting relative movement thereof in the opposite direction.

8. A packaging machine of the character described comprising a frame, a die for supporting an object interposed between sheets of wrapping material, a carrier pivotally supported on said frame, a sealing head pivotally mounted in said carrier at a position adjacent said die, a treadle mounted on said frame, and resilient means connecting said treadle and said carrier in such manner that the sealing head may be moved into engagement with said sheets and said die upon movement of the treadle.

9. A packaging machine of the character described comprising a frame, a die for supporting an object interposed between sheets of wrapping material, a carrier pivotally supported on said frame, a sealing head pivotally mounted in said carrier at a position adjacent said die, a treadle mounted on said frame, resilient means connecting said treadle and said carrier in such manner that the sealing head may be moved into engagement with said sheets and said die upon movement of the treadle, and means independent of said resilient connecting means for applying pressure to the sealing head while the latter is engaged with said die and during movement of the treadle. v

10. In a packaging machine for applying and sealing an envelope about an object, a die for supporting the object to be wrapped between sheets of wrapping material provided with fusible surfaces, a sealing head housing, a plunger carried by said housing and mounted to reciprocate therein, said plunger having a portion complemental to said die, means for yieldably limiting relative movement of the plunger and housing in one direction, and positively limiting relative movement thereof in the opposite direction, and means for applying pressure to the sealing head during engagement thereof with said die.

11. In a packaging machine for applying and sealing an envelope about an object, a die for supporting the object to be wrapped between sheets of wrapped material, a clamp ring having a central aperture therein enclosing said die and spaced relative to the latter in such manner as to provide an annular slot, a sealing head housing movably supported adjacent to said die, means for moving said housing into and out of contact with said sheets of wrapping material and said die, a plunger mounted to reciprocate within said housing, means for yieldably limiting relative movement of the plunger and the. housing in one direction and positively limiting relative movement thereof in the opposite direction, and a cutter carried by said housing and complemental to said annular slot.

FREDERICK C. BUSCHE. 

